This proposal describes a five year career development plan focused on providing the principle investigator (PI) a strong foundation on which to build a successful academic research program. The long-term goal of the PI is to lead a strong NIH funded research program. In the short term this proposal will allow the PI to develop independent lines of research that are both scientifically important and generate a clear change in direction from his current mentor. Work funded by this award will take place at the University of Minnesota in the laboratory of Dr. Joseph Metzger. Dr. Metzger is a noted authority on the utilization of gene transfer technologies to understand cardiac physiology and disease. He is the chair of the department of Integrative Biology and Physiology and has a long track record of successful post-doctoral fellows and graduate students, many of which have gone on to successful careers in academia. In addition to the skills and mentoring of Dr. Metzger, the PI has cultivated a strong network of collaborators and advisors to provide scientific and career advice. The research will focus on the control of coronary artery blood flow in dystrophic cardiomyopathy. Both clinical studies and animal models of muscular dystrophy provide evidence that the regulation of coronary flow is abnormal in muscular dystrophies. The experiments proposed here focus on models of Duchenne muscular dystrophy and limb girdle muscular dystrophy (2C and 2F). The specific aims are: 1) To evaluate the role of dystrophin and sarcoglycan complex in the modulation of coronary flow in response to changes in endothelial shear stress and hormonal mediated vasoconstriction and vasodilation. 2) To determine the mechanistic link between neuronal nitric oxide synthase (nNOS) and dystrophin in the auto-regulatory control of blood flow in the heart. This work will represent the first detailed examination of coronary blood flow regulation in dystrophic cardiomyopathy. The University of Minnesota provides an excellent environment for basic cardiovascular research. The Lillihei Heart Institute provides excellent core resources and a strong collaborative environment. In short, this environment provides all of the resources required for the PI to develop strong independent lines of investigation.